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vishalsaswade · Sep 13, 2007, 12:22 AM

Dear all,

How to identify which computer in the network is broadcasting?what r the reasons that PC strats broadcasting in the network... please reply n help the needful

benn11 · Sep 13, 2007, 01:16 AM

You can use wire shark to capture your network packets and the reason for a computer to broadcast packets is because of unknown destination, so it sends the packets to all known routes.

cajalat · Sep 13, 2007, 04:10 AM

benn11 was correct. To be more specific as far as "unknown destinations" the broadcasts are sent to unknown "local" destinations. If it doesn't know about a destination to yahoo.com for instance then it only needs to know the mac address of its default gateway. Another reason a PC is broadcasting could be due to faulty NIC. I've seen this too many times where a faulty NIC could flood the network.

Wireshark as benn11 mentioned is probably your best starting point for troubleshooting broadcast issues.

retsoksirhc · Sep 13, 2007, 04:22 AM

I've never heard of wireshark... but you could use any packet sniffer really... Microsoft provides one called NetMon, there is a free version and a pay version. The free version should be able to pick up broadcasts and tell you where they come from.

And a PC might broadcast when it first gets on the network. That's how they find a DHCP server to get an IP address, if they're set to acquire one automatically.

cajalat · Sep 13, 2007, 04:28 AM

Wireshark used to be know as ethereal. It is an excellent and fairly complete sniffer for windows. It is also free and is well established.

retsoksirhc · Sep 15, 2007, 06:31 PM

Originally Posted by cajalat

Wireshark used to be know as ethereal. It is an excellent and fairly complete sniffer for windows. It is also free and is well established.

Ah, good ol ethereal. I've not used it in ages. It's got a following now? It used to be mainly for ARP poisoning...